Automatic density control for rolling-compressing machines

ABSTRACT

A self-actuating skew-angle control system in which a planetary drive is employed at the driving end of a rolling-compressing channel with the roller ends being mounted in the housing of a planetary gear drive so that an increase in the rolling resistance caused by the increase of material within the channel results in rotation of the gear drive housing to cause skewing of the driven ends of the rollers against a predetermined bias force resulting in the material being moved axially out of the discharge end of the channel.

United States Patent [191 Molitorisz 1 Sept. 10, 1974 1 AUTOMATIC DENSITY CONTROL FOR ROLLING-COMPRESSING MACHINES [75] Inventor: Joseph Molitorisz, Bellevue, Wash.

[73] Assignee: Rotopak Systems Inc., Bellevue,

Wash.

[22] Filed: Apr. 13, 1972 [21] Appl. No.: 243,641

[52] US. Cl 100/89, 100/40, 100/45 [51] Int. Cl..... B30b 3/04, B30b 13/00, B30b 15/30 [58] Field of Search 100/89, 45, 47, 40, 86,

l00/DIG. 7; 56/1 [56] References Cited UNITED STATES PATENTS 3,269,098 8/1966 Bushmeyer et a1. 100/89 3,408,925 11/1968 Bushmeyer 100/89 FOREIGN PATENTS OR APPLICATIONS 1,657,334 2/1971 Germany 100/89 Primary Examiner-Peter Feldman Attorney, Agent, or Firm-Seed, Berry, Vernon & Baynham [5 7] ABSTRACT A self-actuating skew-angle control system in which a planetary drive is employed at the driving end of a rolling-compressing channel with the roller ends being mounted in the housing of a planetary gear drive so that an increase in the rolling resistance caused by the increase of material within the channel results in rota tion of the gear drive housing to cause skewing of the driven ends of the rollers against a predetermined bias force resulting in the material being moved axially out of the discharge end of the channel.

3 Claims, 2 Drawing Figures AUTOMATIC DENSITY CONTROL FOR ROLLING-COMPRESSING MACHINES BACKGROUND OF THE INVENTION 1. Field of the Invention This invention pertains to apparatus for automatically skewing the rollers of a rolling-compressing machine to impose an axial force on the material to discharge it from the channel.

2. Description of the Prior Art Rolling-compressing is well known in the art and is a compaction technique of the type in which sheets of fibrous material are continuously rolled into a compact core by the imposition of radial, axial and tangential forces in a core-forming channel defined by a plurality of circumferentially spaced rollers. Rollingcompressing apparatus of cylindrical, conical or hyper boloid channel configurations have been developed in the past. For example, US. Pat. No. 3,269,098 illustrates a plurality of rollers in a rolling-compressing channel with the ends of the rollers at the discharge end of the channel being mounted for limited skewing. In this patent, however, the skewing is used solely to preset the skew angle of the channel for various types of material to be formed into the core. German'Offenlegungsschrift 1,657,334 illustrates a plurality of rollers defining a rolling-compressing channel in which the ends of the rollers at the discharge end of the channel are mounted for limited skewing automatically in response to the torque created by the material compressed.

It has been discovered that the device illustrated in I the Offenlegungsschrift 1,657,334 does not provide the necessary sensitivity between increases in the amount of material in the channel and adjustment of the skew angle in response to these increases in the amount of material. The difi'lculty occurs in part because the increase in material is sensed and skew angle adjustment made at the discharge end of the channel where the structure of the core is already well developed.

SUMMARY OF THE INVENTION It is an object of this invention to provide a highly responsive automatic skewing device that skews the roller ends at the driving end of the channel.

It is another object of this invention to provide an automatic skewing device in which the drive train senses the increase in resistance torque caused by the material in the channel and directly converts this to skewing of the housing of the drive train in which the rollers are mounted.

It is still another object of this invention to provide a skew-angle control system which utilizes the inherent forces acting in the drive mechanism of the roller system without any external sensing device to determine increases in the amount of the material within the channel.

As will be readily apparent, this invention is directed toward automatic skew-angle control of a type which is practical, commercially feasible and highly responsive. The invention is applicable equally to either stationary or mobile compressing machines.

The unique feature of the skew-angle control is that it utilizes the inherent forces acting in the drive mechanism of the roller system without any external sensing device and provides the skew at the driving end of the channel where the core is not yet structurally well defined. By eliminating any external sensing devices, whether mechanical, hydraulic or electrical, any delay necessary to convert the signal sensed to a responsive action for varying the skew angle is eliminated and, furthermore, the complexity necessary when using such external sensing devices in an interconnected actuating mechanism is thus also eliminated. By providing the skew angle adjustment at the driving end of the channel, the system is provided with the reliability and response necessary for a commercially feasible machine.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic isometric of the roll-forming channel embodying the principles of the invention.

FIG. 2 is a side elevation of the channel shown in FIG. 1 as shown viewed from the driving end of the machine.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The principles of the present invention are illustrated for purposes of description as embodied in agricultural or industrial mobile or stationary rolling-compressing machines of the type shown in Molitorisz US. patent application Ser. No. 121 ,700, filed March 8, 1971, now US. Pat. No. 3,691,941. Details of the machine are not illustrated for clarity, it being understood, however, that the construction of the roll-forming channel of this invention is substantially the same as that shown in said patent application.

Rollers, identified as 10, l1, l2 and 13 in this specification, are mounted in a discharge end plate 14 and an inlet end plate 16, which in the present embodiment is a part of the gear box housing, as will be described. Although not shown, the discharge ends of the forward rollers 11 and 12 are spring-biased to open radially as shown in application Ser. No. 121,700, as the material fed into the channel increases. Also, as shown in application Ser. No. 121,700, the end plate 14 may be mounted to allow limited preset skewing of the discharge end of the rollers, if desired. As will be seen in the present embodiment all of the skewing is obtained at the driving end of the channel. As is well known, material such as hay isfed between the forward rollers 11 and 12 which are spaced apart sufficiently to provide a transverse inlet opening to allow the material to enter transversely into the channel. Discharge of the rolled core occurs axially through the discharge end plate 14.

In accordance withthe teachings of this invention the skewed rollers provide the axial force for discharging the core from the channel. This axial force is available only when the rollers are skewed and not when the rollers are in parallel alignment. Thus, in case of a mobile agricultural machine material fed into the channel will accumulate within the channel until the rollers are skewed and begin the axial movement of the material in the channel. It is highly desirable in a mobile agricultural machine that the material remain in the channel until a sufficient accumulation has occurred to form the core into the desired size and density. In most existing mobile machines the feeding rate into the channel is not sufficiently constant to continually produce acore of a desired size and density. Therefore, the core must be held in the channel until the desired amount of material has entered the channel. In the instant invention this control is obtained by automatically adjusting the skew angle of the driven ends of the rollers to provide the necessary axial force on the core only after the core has reached the desired size and density. It is obvious, of course, that a delicate balance must be obtained between core size and density and skew angle adjustment to assure smooth operation of the machine and a high quality core.

The highly responsive skew angle control of this invention is provided by a planetary drive system 18. The planetary drive system includes a gear boxhousing 16 (in this case forming the end wall for supporting the rollers) rotatably mounted in the rolling-compressing machine frame 20. Rotational movement of the housing 16 relative to the frame 20 is resisted by a biasing spring 22. The spring is fixed by a bracket 24 at one end to the housing 16. The other end of the spring is connected to an adjusting mechanism 26 which is secured by a bracket 28 to the frame 20. Thus, rotation of the housing inthe clockwise direction as viewed in FIG. 1 occurs against the bias of the spring with the spring tension being adjustable by the adjusting mechanism 26.

The rollers 10-13 are provided with shafts 10a-13a, respectively, which are journaled in the housing 16 and keyed to a plurality of planetary gears 30, 31, 32 and 33, respectively. A central sun or drive gear 36 is keyed to a central shaft 38 which is journaled for rotation by a bearing block 40 that is fixed to the frame 20. The power input shaft 38 is rotated by any conventional means in a clockwise direction, as viewed in FIG. 1. The sun gear attached to the center shaft distributes the power to the planetary gears and the sahfts of the rollers. The rollers are flexibly attached to the shafts 10al3a, as illustrated, for example, in said patent application, Ser. No. 121,700, to allow angular motion (pendulum motion) in 360 and also provide positive torque transfer from the shafts to the rollers. A rotation limiting mechanism is provided to limit the rotation of the housing 16 and includes a plate 40 mounted on the housing. The plate moves with the housing into engagement with an adjustable stop 42 secured to the frame 20.

When the channel is empty, the biasing spring 22 positions the housing 16 such that the axes of the rollers are parallel. Therefore, no axial velocity components are being produced by the rotating rollers. As the channel begins to fill with incoming sheets of fibrous material the rolling resistance on the rollers increases. When the torque produced by the rolling resistance of the core being formed in the channel reaches an equilibrium with the torque produced by the biasing spring 22, a rotational displacement of the housing 16 will occur and the extent of this displacement will be directly related to the differential magnitude of the two counteracting torques. The maximum limit of this rotational displacement is determined by the position of the limiting means 42. With a decrease in the rolling resistance the ratio of the two counteracting torques changes and the magnitude of the rotational displacement of the housing also changes. It can be readily seen that the rotational displacement of the main gear box is in the direction of rotation of the core formed in the channel, that is, clockwise, as viewed in FIG. 1. Such displacement changes the position of the axes of the rollers relative to the axis of the core, thus skewing the rollers to exert axial forces on the core in the direction of the discharge end of the channel. The magnitude of these axial forces is directly related to the magnitude of the skew angle. Since the biasing spring is adjustable, the equilibrium between the two counteracting torques can be set at any desired level, thus, the minimum density of the discharge core can be determined. Similarly, by making the position of the limiting means 40 adjustable, the magnitude of the maximum skew angle can be determined.

The method of this invention directly relates the in crease in rolling resistance on the rollers to the skew angle adjustment at the driven ends of the rollers by sensing the resistance force at a planetary drive for the rollers. Thus, the method is highly responsive and extremely sensitive to provide an accurate balance between rolling resistance and skew angle.

While the preferred embodiments of the invention have been illustrated and described, it should be understood that variations will be readily apparent to one skilled in the art without departing from the principles described herein. accordingly, the invention is not to be limited to the specific embodiments illustrated, but rather is to be limited solely by a literal interpretation of the claims appended hereto.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A roller-compressing apparatus of the type employing circumferentially spaced rollers defining a rollforming channel having a transverse material inlet and an axial discharge for compressing loose fibrous materials into a continuous roll, the improvement comprising a frame, means for rotatably supporting the ends of the rollers on said frame at the discharge end of said channel, means for rotatably supporting and driving the roller driven ends at the driving end of channel and for skewing the roller driven endsin response to resistance to rolling caused by the material forming a roll in the channel, said skewing providing an axial force component on said material to move the compressed roll axially through said channel discharge, and means for biasing said rolls into an unskewed position whereby the amount of skew is directly dependent upon the counter force imposed by the biasing means.

2. The apparatus of claim 1, including adjustable limiting means for limiting the amount of skew in said rollers.

3. The apparatus of claim 2 wherein said driving, supporting and skewing means includes a housing having a wall, for supporting said roller driven ends said housing being mounted on said frame for limited rotational movement, said biasing means and said adjustable limiting means being connected to said housing for resisting and limiting rotation of the housing, a plurality of driven planetary gears within said housing and connected to said roller driven ends, a central sun gear for rotating said driven planetary gears, and means rotating said central sun gear for rotating said driven planetary gears and said housing when rotation of said driven planetary gears is resisted by the material acting against said rollers. 

1. A roller-compressing apparatus of the type employing circumferentially spaced rollers defining a roll-forming channel having a transverse material inlet and an axial discharge for compressing loose fibrous materials into a continuous roll, the improvement comprising a frame, means for rotatably supporting the ends of the rollers on said frame at the discharge end of said channel, means for rotatably supporting and driving the roller driven ends at the driving end of channel and for skewing the roller driven ends in response to resistance to rolling caused by the material forming a roll in the channel, said skewing providing an axial force component on said material to move the compressed roll axially through said channel discharge, and means for biasing said rolls into an unskewed position whereby the amount of skew is directly dependent upon the counter force imposed by the biasing means.
 2. The apparatus of claim 1, including adjustable limiting means for limiting the amount of skew in said rollers.
 3. The apparatus of claim 2 wherein said driving, supporting and skewing means includes a housing having a wall, for supporting said roller driven ends said housing being mounted on said frame for limited rotational movement, said biasing means and said adjustable limiting means being connected to said housing for resisting and limiting rotation of the housing, a plurality of driven planetary gears within said housing and connected to said roller driven ends, a central sun gear for rotating said driven planetary gears, and means rotating said central sun gear for rotating said driven planetary gears and said housing when rotation of said driven planetary gears is resisted by the material acting against said rollers. 